20814881 has 4 divisors (see below), whose sum is σ = 21298992. Its totient is φ = 20330772.

The previous prime is 20814869. The next prime is 20814883. The reversal of 20814881 is 18841802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20814881 is a prime.

It is a super-2 number, since 2×20814881² = 866518542088322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20814883) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 241991 + ... + 242076.

It is an arithmetic number, because the mean of its divisors is an integer number (5324748).

Almost surely, 2^20814881 is an apocalyptic number.

It is an amenable number.

20814881 is a deficient number, since it is larger than the sum of its proper divisors (484111).

20814881 is an equidigital number, since it uses as much as digits as its factorization.

20814881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 484110.

The product of its (nonzero) digits is 4096, while the sum is 32.

The square root of 20814881 is about 4562.3328462531. The cubic root of 20814881 is about 275.0793423954.

The spelling of 20814881 in words is "twenty million, eight hundred fourteen thousand, eight hundred eighty-one".